A Remote Carrier Synchronization Technique for Coherent Distributed Remote Sensing Systems

TL;DR

This paper introduces a novel remote carrier synchronization method for distributed remote sensing systems, focusing on satellite or airborne nodes, using a full-duplex approach with multiple carriers to improve phase coherence.

Contribution

It proposes a general system model and a distributed phase synchronization loop that addresses self-interference and Doppler effects in satellite communication links.

Findings

Effective synchronization under phase noise and Doppler shifts

Simulation results validate the proposed algorithm's robustness

Guidelines for implementing synchronization in spaceborne systems

Abstract

Phase, frequency, and time synchronization are crucial requirements for many applications, such as multi-static remote sensing and communication systems. Moreover, the synchronization solution becomes even more challenging when the nodes are orbiting or flying on airborne or spaceborne platforms. This paper compares the available technologies used for the synchronization and coordination of nodes in distributed remote sensing applications. Additionally, this paper proposes a general system model and identifies preliminary guidelines and critical elements for implementing the synchronization mechanisms exploiting the inter-satellite communication link. The distributed phase synchronization loop introduced in this work deals with the self-interference in a full-duplex point to point scenario by transmitting two carriers at each node. All carriers appear with different frequency offsets around a central frequency, called the application central-frequency or the beamforming frequency. This work includes a detailed analysis of the proposed algorithm and the required simulations to verify its performance for different phase noise, AWGN, and Doppler shift scenarios.